Conceptual Design Study on Advanced Aqueous Reprocessing System for Fast Reactor Fuel Cycle

Batch Crystallization of Uranyl Nitrate

“…These advantages of crystallization have motivated the proposal of new reprocessing concepts. Two concepts in particular have prompted developmental studies in Japan: the NEXT (New EXtraction System for TRU Recovery) process 4) and the U-Pu Co-crystallization process. [5][6][7] The NEXT process, which is designed for fast reactor fuel, is based on the PUREX process.…”

“…For these reprocessing processes, uranium has to be recovered by crystallization from a dissolver solution of spent fuel, where the concentration of uranium is higher than the usual dissolver solution in the PUREX process in order to recover as much uranium as possible. 4) For this purpose, a uranium concentration of 500 g/l is estimated from the equilibrium data, whereas a uranium concentration of about 300 g/l is assumed when the crystallization is applied to U-purification in the PUREX process. 2,3) Kurashima et al 10) examined uranium crystallization aiming at its application to a dissolver solution of spent fuel.…”

Plutonium and other actinides behaviour in NEXT process

“…For meeting these requirements, the investigation and the evaluation of several conceptual reactors, reprocessing and fuel fabrication for the future fast reactor cycle system have been carried out in the feasibility study. On this investigation and evaluation, the advanced aqueous reprocessing system named New Extraction system for TRU (Np, Pu, Am and Cm) recovery (NEXT) process is selected as one of the promising processes for a spent nuclear fuel reprocessing [1]. The NEXT process basically consists of three characteristic processes as shown in Fig.…”